One known type of information storage device is a disk drive device that uses magnetic media to store data and a movable read/write head that is positioned over the magnetic media to selectively read from or write to the magnetic media.
FIG. 1 illustrates a conventional disk drive device and show a magnetic disk 101 mounted on a spindle motor 102 for spinning the disk 101. A voice coil motor arm 104 carries a head gimbal assembly (HGA) 100 that includes a slider 110 incorporating a read/write head. A voice-coil motor (VCM, not labeled) is provided for controlling the motion of the motor arm 104 and, in turn, controlling the slider 110 to move from track to track across the surface of the disk 101, thereby enabling the read/write head to read data from or write data to the disk 101. In operation, a lift force is generated by the aerodynamic interaction between the slider 110, incorporating the read/write head, and the spinning magnetic disk 101. The lift force is opposed by equal and opposite spring force which is applied by the HGA 100 such that a predetermined flying height above the surface of the spinning disk 101 is maintained over a full radial stroke of the motor arm 104.
Now referring to FIG. 2a and FIG. 2b, the conventional HGA 100 includes a slider 110 having a reading/writing head imbedded therein, a suspension 120 to load or suspend the slider 110 thereon. As illustrated, the suspension 120 includes a load beam 130, a base plate 140, a hinge 150 and a flexure 160, all of which are assembled together.
As illustrated in FIG. 3a and FIG. 3b, pluralities of electrical traces 161 are formed on the flexure 160 along length direction thereof. One end of the electrical traces 161 are electrically connected to six electrical pads 162 which are formed on the suspension tongue 163, and the other end of the electrical traces 161 are electrically connected to an outer control system (not shown). A trailing surface 111 of the slider 110 has six connection pads 112 corresponding to the six electrical pads 162. Concretely, the connection pads 112 are electrically connected to the electrical pads 162 by solder joints 164, thus connected to the electrical traces 161, thereby electrically connecting the slider 110 to the electrical traces 161. After the slider 110 mounted on the suspension tongue 163 and electrically coupled with the electrical pads 162 by the connection pads 112, the outer control system can control the slider 110, thus realizing data reading/writing operation with respect to the disks 101.
As indicated above, the number of the connection pads 112 formed on the trailing surface 111 of the slider 110 is six. The connection pads 112 are arranged to be one row and adjacent to a mounting surface which face to the suspension tongue 163 for bonding with the electrical pads 162 disposed on the suspension tongue 163 and testing the performance of the slider before bonding. And all of the connection pads 112 are used to electrically connect the inner sensors of the slider 110 to an outer control system (not shown) by the electrical traces 161. Concretely, there are three inner sensors embedded into the slider 110. Every two connection pads 112 are connected to one inner sensor. Wherein one pair of the connection pads 112 are electrically connected to a read head (not shown) adapted for reading data from the disk, another pair of pads 112 are electrically connected to a write head (not shown) adapted for writing data to the disk, and the other two connection pads 112 are electrically connected to a thermal resistance to heat the pole tip formed on an air bearing surface 113 of the slider 110 which facing to the disk 101 and then make the pole tip extrude, thereby improving the precision of reading and writing of the slider 110.
However, on one hand, the slider is required to become more and more smaller. This, in turn will result in smaller space between the connection pads. While bonding the connection pads to the electrical pads of the suspension tongue, the precision control is required to prevent short circuit. That is to say, it becomes difficult to bond the smaller slider to the suspension.
On the other hand, consumers are constantly desiring greater storage capacity for such disk drive devices, as well as faster and more accurate reading and writing operations. Thus, disk drive manufacturers have continued to develop higher capacity disk drives by, for example, increasing the density of the information tracks on the disks by using a narrower track width and/or a narrower track pitch. However, each increase in track density requires that the disk drive device has a corresponding increase in the positional control of the read/write head in order to enable quick and accurate reading and writing operations using the higher density disks. As the track density increases, it becomes more and more difficult using known technology to quickly and accurately position the read/write head over the desired information tracks on the storage media. Thus, disk drive manufacturers are constantly seeking ways to improve the positional control of the read/write head in order to take advantage of the continual increase in track density.
One approach that has been effectively used by disk drive manufacturers to improve the positional control of read/write heads for higher density disks is to adopt a series of sensors, such as vibration sensor, head disc interface sensor (HDI sensor) and so on. If the additional sensors are set outside the slider, the electrical signal of the sensors will be delayed inevitably as a result the slider can not be adjusted in time. Thus it requests all the increased sensors to be set inside the slider to improve the performance of the slider.
However, more sensors are embedded into the slider, more connection pads need to be disposed on the slider. But the slider is limited to 700 μm in width at present, and it requests to keep enough space between each two connection pads to prevent short circuit. Furthermore, in order to meet the request of bonding, the connection pads must be arranged to be one row, and in order to meet the request of testing, the dimension of each connection pad is limited to 60 μm×60 μm at least. Therefore, conventional layout of the connection pads makes the slider difficult to provide additional pads thereon.
Accordingly, it is desired to provide a slider with a new pad layout to facilitate bonding of the connection pads and permit to provide additional pads thereon to connect the additional sensors therein for precise reading and writing to overcome the above-mentioned drawbacks.